'ub' Dialect

Operation definition ¶

ub.poison (ub::PoisonOp) ¶

Poisoned constant operation.

Syntax:

operation ::= `ub.poison` attr-dict (`<` $value^ `>`)? `:` type($result)

The poison operation materializes a compile-time poisoned constant value to indicate deferred undefined behavior. value attribute is needed to indicate an optional additional poison semantics (e.g. partially poisoned vectors), default value indicates results is fully poisoned.

Syntax:

poison-op ::= `poison` (`<` value `>`)? `:` type

Examples:

// Short form
%0 = ub.poison : i32
// Long form
%1 = ub.poison <#custom_poison_elements_attr> : vector<4xi64>

Traits: AlwaysSpeculatableImplTrait, ConstantLike

Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface)

Effects: MemoryEffects::Effect{}

Attributes: ¶

Results: ¶

Attribute definition ¶

PoisonAttr ¶

Syntax: #ub.poison